The present invention relates to a pallet structure designed to support the central tubes of cylindrical objects of variable outside diameter, said structure comprising a base portion of generally rectangular shape with uprights secured at each of it four corners. The invention also discloses holder members which are used with the pallet and which support the ends of the central tubes of such cylindrical bodies.
A large variety of pallets or containers of generally parallelepiped shape are known which are designed to hold and retain parts of a specific shape such as cylindrical or spherical vessels or rolls or coils of striplike material which are of generally cylindrical shape. The pallets or containers are designed to be handled by a forklift truck the tines of which support the base portion of the pallet typically loaded with rolls, which are loaded from above. In a known design of a pallet for carrying rolls, semi-cylindrical support members are provided which constitute bearing surfaces that are integral with the walls of the pallet, and these are used to support specially designed cylindrical pin members which are fitted into the central tube around which the rolls of striplike materials are wound. The semi-cylindrical support members are rigidly secured to the walls of the pallet thus making it possible to create a rigid and fairly solid structure. Experience has however shown that such a pallet structure does not have the required flexibility of use and is generally only suitable for transporting one single type of roll. Attempts to provide a pallet suitable for transporting rolls of film material of different sizes gave rise to a complex pallet structure including numerous semi-cylindrical support members which were permanently attached to the walls thereof, with the result that the pallet is expensive to produce. Additionally, during unloading, the rolls sometimes collide with the walls of the pallet and it was necessary to provide a special packaging for the rolls of film.
It is hence a principal object of the present invention to provide a pallet which is readily adaptable to the transporting of several types of roll without requiring the use of disposable packaging material and the associated problems of pollution when disposing of it, at a relatively limited cost.
A further object of the invention is to provide a pallet which, while being suitable for transporting numerous types of rolls of differing diameter and axial length, includes modular components for supporting the ends of the central tube of such rolls, with it being possible to readily change the place of such modular components or replace one by another, thus leading to a corresponding reduction in the costs of manufacturing and assembling the pallets.
A further object of the invention is to provide a pallet of generally parallelepiped shape in which it is possible to arrange rolls of film or striplike material constituting cylindrical objects incorporating a central support tube in either of the two principal directions (lengthwise and widthwise) of the pallet.
It is a further object of the invention to provide pallets which can be readily stacked or fitted one on top of the other and which are truly universal as regards their capacity to accommodate rolls of any dimensions with the possibility of locking the rolls in position inside the pallet structure.
A further object of the invention is to provide special end holders for the two ends of the central tube of such rolls which can either be extracted in the upwards direction from special recesses designed to receive them or can be removed axially by turning them through 90.degree.. Such holders must enable a lifting bar to be introduced axially into the central tube of the cylindrical object to enable the latter to be lifted out of the pallet by lifting apparatus acting on said bar.
A further object of the invention is to facilitate loading and unloading of rolls of film material by eliminating the intermediate steps of packing and unpacking such rolls and, as a consequence, reducing the risks of contamination and damaging of the film material carried on such rolls while eliminating any recourse to conventional packing means such as wooden pallets, cardboard boxes, and intermediate and final packages using plastics material.